The present invention relates to the field of communications and more particularly to radiotelephone communications.
It has been proposed to provide global positioning features in cellular radiotelephones. For example, U.S. Pat. No. 5,235,633 to Dennison et al. discusses a cellular telephone system that uses the position of a mobile unit to make call management decisions. In particular, each mobile unit includes a global positioning system (GPS) receiver that receives information from a constellation of satellites to determine the precise location of the mobile unit. This position information is relayed to the cell site initially managing the mobile unit, and the mobile unit is handed off to a cell site that is most appropriate for the call.
In addition, U.S. Pat. No. 5,625,668 to Loomis et al. discusses a positioning reporting cellular telephone. The cellular telephone of this patent includes a global positioning system (GPS) receiver and a cellular transceiver. In addition, a data processing facility converts latitude, longitude, velocity, and bearing information provided by the GPS receiver into meaningful descriptors that are spoken with a speech synthesizer. The disclosures of both of these patents are hereby incorporated herein in their entirety by reference.
Portable radiotelephones including GPS receivers have typically used an additional antenna to provide GPS reception. For example, quadrafilar helix antennas extending from the radiotelephone body have been used. The size constraints on these antennas, however, may reduce the gain available using quadrafilar helix antennas. Moreover, these antennas may be oriented at less than ideal angles and/or may be too close to the user""s body when used during telephone communications further reducing gain. Accordingly, there continues to exist a need in the art for improved antennas for GPS receivers incorporated into radiotelephones.
It is therefore an object of the present invention to provide improved antennas for cellular radiotelephones.
It is another object of the present invention to provide improved antennas for cellular radiotelephones including GPS receivers.
These and other objects are provided according to the present invention by a radiotelephone including a patch antenna including a conductive layer for receiving electromagnetic signals. In particular, the patch antenna can be used to receive global position signals in a radiotelephone including global position (GPS) features. Accordingly, the patch antenna can be included in/on the radiotelephone body without significantly affecting the dimensions thereof.
In the past, patch antennas have not generally been used in portable radiotelephones because the vertical orientation of the radiotelephone against the user""s head, as occurs during normal radiotelephone use, is not desirable for patch antenna reception and gain. The inventors have realized, however, that a patch antenna can be used advantageously during radiotelephone GPS operations because the radiotelephone can be held horizontally away from the user""s head. Moreover, the patch antenna can be added to the radiotelephone without significantly affecting the dimensions of the radiotelephone because the patch antenna can be incorporated substantially parallel to a face of the radiotelephone body.
In particular, a portable radiotelephone according to the present invention can include a transceiver, a processor, a speaker, a microphone, and a patch antenna. The transceiver transmits and receives radiotelephone communications, and the processor processes the radiotelephone communications transmitted and received by the transceiver. The speaker generates sound responsive to the received radiotelephone communications, and the microphone generates electrical signals for the transmitted radiotelephone communications responsive to outside sound. The patch antenna includes a conductive layer coupled to at least one of the processor and the transceiver.
More particularly, the patch antenna can be a global position patch antenna that receives electromagnetic global position signals from global position satellites, and the processor can include a global position receiver that determines a position of the radiotelephone based on the received electromagnetic global position signals.
The portable radiotelephone can include a radiotelephone body housing the speaker, the microphone, the transceiver, and the processor. In addition, an opening can be provided through the radiotelephone body adjacent the speaker to allow the generated sound from the speaker to pass therethrough, and the patch antenna can be located adjacent the speaker with an opening therein aligned with the opening in the face of the radiotelephone body to allow the generated sound from the speaker to pass therethrough.
Alternately, the patch antenna can have an opening therein aligned with another opening in the radiotelephone body to allow outside sound to pass through to the microphone. According to another alternative, the patch antenna can be adjacent to a keypad and have an opening therein aligned to allow a key of the keypad to move therethrough.
The radiotelephone can also include a display coupled to the processor wherein the processor generates a message on the display during global position calculations to encourage a horizontal orientation of the patch antenna. For example, the display might instruct the user to wait with the radiotelephone in a horizontal position held away from the user""s body until the global position calculations have been completed.
The patch antenna can be provided, for example, by a conductive layer on a dielectric substrate inside the radiotelephone body. Alternately, the conductive layer can be provided on a surface of the radiotelephone body thereby eliminating the need for a separate dielectric layer. In other words, the radiotelephone body can be formed of a plastic that does not significantly attenuate the global position signals received from the global position satellites, and the conductive layer of the patch antenna can be formed as a part of the radiotelephone body. Furthermore, the conductive layer can be formed on either an inside or outside surface of the radiotelephone body. Furthermore, the patch antenna can be provided on a flip portion of the radiotelephone body.
The radiotelephones, and methods of the present invention can thus be used to provide a global position antenna within a portable radiotelephone without significantly affecting the dimensions of the radiotelephone. The radiotelephones, and methods of the present invention can also provide improved reception of GPS signals.